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Section 4 – Clearances – Directory Page

4.1 Meter Clearances and Locations 20

4.2 Clearances of Overhead Service 23

4.3 Conductors Near Pools, Spas, or Hot Tubs 30

4.4 Clearance from Hazardous (Classified) Locations 31

4.5 Free-Standing Meter Socket Clearances from Permanent Power Company Equipment 31

4.6 Clearances Between Equipment Pads and Buildings 32

4.7 Firewalls (Blast Walls) 33

2016 Electric Service Requirements, 4th Edition Section 4

This manual shall be distributed and interpreted in its entirety. Individual pages will not represent all the requirements necessary for an

installation. © 2019 PacifiCorp.

19

4.Cle a ra n c e s

Clearances

This section provides information on required clearances for meter sockets, clear working space,overhead services, and underground services.

4.1 Meter Clearances and Locations

The customer must provide suitable location, space, and provisions for mounting a metersocket, which must be approved in advance by the Power Company.

All metering equipment shall be installed in locations that are accessible to Power Companyemployees and their equipment.

Metering equipment shall not be installed in the following locations unless approved by thePower Company:1. Any unsafe location, as determined by the Power Company

2. Any hazardous location, as defined by the NEC, for electrical equipment3. Directly over any windowwell, stairway, ramp, or steps4. In any entryway5.Within 36 inches (36″) of a window that has a view of living space or restrooms, or within 36inches (36″) of a door (guideline).

6. In any place where moisture, fumes, or dust may interfere with the meter’s operation or maydamage the meter, as determined by the Power Company

7. On any surface subject to excessive vibration, as determined by the Power Company

Section 4 2016 Electric Service Requirements, 4th Edition

8. On Power Company poles or equipment9. In an area where metering equipment is likely to be fenced in10. Where the meter face or the door to the metering equipment is obstructed11. Where the door to the metering equipment is on (or recessed in) an external surface builtwithin seven feet (7′) of a property line, alleyway, or driveway, except when expressly per-mitted in advance by the Power Company

12. On the drive-through side of a building13. Onmobile structures such as, but not limited to trailers, barges, cranes, dredges, draglines,mobile pumping equipment, boat slips, or floating dwelling units such as houseboats

14. Meters shall not be blocked by anymaterials, including shrubs, landscaping, orother vegetation

15. Closer than 36 inches (36″) horizontally from gasmeters, gas valves, fixed or threaded fit-tings, separable valves or unions, or regulators (See ESRWhite Paper 4—Pipe Fittings )

16. Areas adjacent to fuel storage units, including permanently-mounted generator fuel tanks.(See ESRWhite Paper 4—Fuel Storage Tanks.)

20 This manual shall be distributed and interpreted in its entirety. Individual pages will not represent all the requirements necessary for an installation. © 2019 PacifiCorp.

Requirements:1. An unobstructed level working space shall be provided per NEC110.26 A, and as shownin Figure 2 and Figure 3.

2. In installations of two or more adjacent meter sockets, additional horizontal clearance isneeded; see Figure 3.

3. For minimum vertical clearance requirements in installations of three or more gangedmeters, refer to Sections 8.3 and 9.1.

4. Equipment or other material that may obstruct the working space is not allowed, includingthe space below the meter.

4.1.2 Residential Meters

The customer must install residential meters outdoors at a location acceptable to the PowerCompany and in accordance with Section 4.2.1, Figure 4 or Section 4.3.1, Figure 7. Themeter shall be located within 10 feet (10′) of the front (street side) corner of the dwelling, onthe side of the dwelling closest to the Power Company’s source, except for remodel ofexisting services, in which case the meter location must be permitted by the AHJ andapproved before installation by the Power Company.

Where there is no suitable location available on the structure, a free-standing meteringinstallation may be used, at a location approved in advance by the Power Company.

4.1.3 Meters in Gated Areas and Enclosed Spaces

Gated outdoor areas and enclosed spaces are not considered accessible. Meteringequipment located within a gated area may be approved on a case-by-case basis; consultthe Power Company prior to installation.

If prior approval for a gated entry is granted by the Power Company, it shall be keyed for aPower Company key or equipped with a Power Company-provided lock box.

For more information, see ESRWhite Paper 4—Gated and Enclosed Spaces..


This manual shall be distributed and interpreted in its entirety. Individual pages will not represent all the requirements necessary for an installation. ©

2019 PacifiCorp.

21

4.1.1 Meter Clearance Dimensions


4.1.4 Access

If a meter is inaccessible (as determined by the Power Company), for example, by installinga deck, fence, or enclosure, the customer shall, at their expense, either modify the area toprovide safe, unobstructed access to the meter, or move the meter socket to a locationacceptable to the Power Company.

Devicesmounted below the meter are not acceptable.

Figure 2—Meter Socket Clearance Requirements


Figure 3—ClearWorkspace Requirements

4.2 Clearances of Overhead Service

The customer shall provide a point of attachment that allowsminimum clearances to be met in allconditions. The clearances listed in Table 6 are required for overhead installations in all statesexcept California. For California clearances, see Table 7. See notes for both clearance tablesfollowing Table 7.

Long services or other special casesmay require additional clearance. Consult the PowerCompany if the service length may exceed 45 feet (45ʹ), if the service will cross uneven or slopedterrain, or for situations not listed in the following tables.




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Table 6—NESC C2-2017 Clearances for Service Drops and Drip Loops, 750 V and Below

Minimum Clearance (Ft.)Non-Coastal Coastal*Description

Service drop clearance (NESC Table 232-1)

16 16.5

16 16.516 16.5

16 16.5

Over roads, streets, and other areas subject to vehicle traffic over eight feet (8′) in height

Over or along alleys, parking lots, and non-residential drivewaysOver land traveled by vehicles

Clearances over residential driveways only (NESC Table 232-1) If installation is subject to vehicle traffic over eight feet (8′) in height

If installation is not subject to vehicle traffic over eight feet (8′) in height:

• for service drops 120/240 & 120 V/208 Y 12 12.5• for drip loops of service drops 120/240 and 120/208 V 10 10.5Clearances over spaces and ways subject to pedestrians/restricted traffic only

(NESC Table 232-1. See note 2, Table 7)12 12.5For nonresidential buildings

For residential buildings only:

• for 277 V/480 Y (NESC Table 232-1 and applicable notes) 10.5 10.5• for 120/240 and 120/208 Y (NESC Table 232-1 and applicable notes) 10 10.5Clearances from building for service drops not attached to the building (NESC Table 234-1)Vertical clearance over or under balconies and roofs and:• accessible to pedestrians 11 11.5• not accessible to pedestrians 3.5 10.5Horizontal clearance to walls, projections, windows, balconies, and areas

5 5.5accessible to pedestriansClearances for service drops attached to a building or other installation (over or along the installation

to which they are attached)From the highest point of roofs, decks, or balconies over which they pass and:• readily accessible (see NESC 234.C.3.d.1) 10 10• not readily accessible (see NESC 234.C.3.d.1, exception 2) 3 3• above a not-readily-accessible roof and terminating at a (through-the-roof)service conduit or approved support, the service and its drop loops set no less than 18” above the roof. No more than 72″ of the service cable passes

over the roof or within 48″ of the roof edge (see NESC 234.C.3.d.1.b)

1.5 1.5

• in any direction from windows designed to open (does not apply to non-coastal service cable above the top level of a window; see NESC 234.C.3.d.2)

3 3

• horizontally from porches, fire escapes, etc. (see NESC 234.C.3.d.3) 5 5• vertically below porches, fire escapes, etc. (see NESC 234.C.3.d.4) 3 3

* Coastal:Coastal areas, such asClatsop, Lincoln, and Cooscounties in Oregon, the northern California seacoast are subject to area-wide contamination. In these coastal areas, the companyuses service cable that includesa covered neutral to prevent corrosion. Thiscable conforms to the definition of covered conductors in NESC Rule 230.D. Elsewhere service cables conform to NESC Rule 230.C.3rules for supply cables.

Ta b le 7


Table 7—MinimumClearances for Service Drops and Drip Loops, California Only

(GO 95), 277/480 V and Below

GO 95 MinimumClearance (ft.)

Service drop clearance

• Crossing or along thoroughfares in urban districtsor crossing thoroughfares in rural districts

18

• Above ground along thoroughfares in rural districts,or across other areas traversed by vehicles or agricultural equpiment

15

• Over private driveways, lanes, or other private property areasaccessible to vehicles used for industrial or commercial purposes

16

• Over private driveways, lanes, or other private property areasaccessible to vehicles used for residential purposes only

12

• Above ground in areas accessible to pedestrians only 10

Clearances from buildings for service drops not attached to the building

• Vertical clearance above walkable surfaces on buildings, bridges, or other structures that do notordinarily support conductors,whether attached or unattached

8

• Vertical clearance above non-walkable surfaces on buildings, bridges, or other structuresthat do not ordinarily support conductors,whether attached or unattached

8

Horizontal and radial clearances

• From fire escapes, exits, windows, and doors 3

• Horizontal clearance of the conductor at rest from building, bridges,or other structures where such conductor is not attached

3

Clearances for service drops near swimming pools

• Consult the Power Companyprior to the installation of pools, spas, or hot tubs

Notes for Clearance Table 6 and Table 7:1. A “truck” is any vehicle exceeding eight feet (8′) in height. Areas not subject to truck trafficinclude placeswhere truck traffic normally doesn’t occur or is not reasonably anticipated.

2. “Spaces and ways subject to pedestrians or restricted traffic only” include those areaswhereequestrians, vehicles, or other mobile units that exceed eight (8′) feet in height are prohibitedby regulations, permanent terrain configurations, or are otherwise not normally encounteredor anticipated.

3. Roofs, balconies, or other areas shall be considered readily accessible to pedestrians if theycan be casually accessed through a doorway, ramp, window, stairway, or permanently-moun-ted ladder, by a person on foot who neither exerts extraordinary physical effort nor employsspecial tools or devices to gain entry. A permanently-mounted ladder is not considered ameans of access if its bottom rung is eight feet (8′) or more from the ground or other per-manently-installed accessible surface (NESC 234.C.3.d, Exception 1).




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4.2.1 Clearances for Buildings Supporting an Overhead Service

Figure 4—Clearances for Buildings Supporting an Overhead Service

Requirements:1. A ten-foot maximum distance from the front corner of a residential building to the far side of themeter is allowed.

2. Table 6 and Table 7 list the minimum drip loop and service drop clearance requirements.3. The cable and drip loop (lowest point) shall be at least 18 inches (18″) above a non-accessibleroof (NESC234.C.3.d, Exceptions 1 and 2).

4.Meters shall not be installed within 36 inches (36″) of a window that has a view of livingspace or restrooms, or within 36 inches (36″) of a door (guideline).

5. The customer must install residential meters outdoors at a location acceptable to the PowerCompany and in accordance with Figure 4.

6. Buildings shall not be constructed under or adjacent to power lines.7. For further details regarding meter clearances and locations, see Section 4.1.


4.2.2 Mast Guying and Bracing

If the point of attachment is more than 36 inches (36″) above a point of support on the mast,two independent guys are required to secure the masthead. Figure 5 and Figure 6 showguyed masts, a braced mast, and anchoring options.

Table 8—Acceptable Service Conductor Lengths forWall-Mounted Meters

Service Mast(Steel Conduit) Service Size

Utility Service Lengthwithout Guying

Utility Service Lengthwith Guying

2” min. 200 A or Less 60’ Maximum 90’ Maximum

2 1/2” min. 201 - 400 A Service 45’ Maximum 90’ Maximum

401 A and Above Consult the Power Company

Note: For clearances, see Section 4.2.

Requirements:1. The service mast shall extend through the roof line except when sufficient height can beobtained to meet the clearances given in Table 6 or Table 7.

2. Where the mast has service cable attached to it, the mast shall be Rigid MetallicConduit (RMC) or Intermediate Metallic Conduit (IMC). IMCmay not be allowed by theauthority having jurisdiction.

3. The mast shall be securely fastened to the building.

4. Conduit coupling shall not be installed between the roof line and the pointof attachment.

5. Guying is required if a coupling is within eight feet (8′) of the weatherhead and locatedabove the last point of securement to the structure.

6. The mast shall be guyed if the point of attachment is more than 36 inches (36″) above theroof line.

7. Guying shall be ¼″ common galvanized steel strand or equivalent, rated at 1,800 lbs. Twoguys are required.

8. Building-mounted masts shall use a rigid steel pipe clamp as the point of attachmentbetween the guy wire and the service mast (except in contaminated and coastal areasstainless steel pipe clamp is required). The point of attachment shall be securely fastenedto a significant structural member.




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Figure 5—Mast Guying, Anchoring, and Bracing


Figure 6—Overhead Service to Wall-Mounted MetersSurface or Flush-Mount Metering (New and Rewire)




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4.2.3 Clearances for Underground Service

Clearances for Underground Service

Figure 7—Clearances for Underground Service

Requirements:1. A ten-foot maximum distance from the front corner of a residential building to the far sideof the meter is allowed.

2. Meters shall not be installed within 36 inches (36″) of a window that has a view of livingspace or restrooms, or within 36 inches (36″) of a door (guideline).

3. The customer shall obtain Power Company approval for the meter locationprior to installation.

4. A minimum of 24 inches (24″) of backfill above underground conduit is required.See Figure 11.

5. For further details regarding meter clearances, see Section 4.1.

4.3 Conductors Near Pools, Spas, or Hot Tubs

4.3.1 Overhead

The Power Company recommends that pools, spas, or hot tubs not be placed below or nearoverhead conductors. Consult the Power Company before placing pools, spas, or hot tubs


below or near overhead conductors.

4.3.2 Underground

Never locate underground conductors under or within 60 inches (60″) horizontally from theinside wall of a pool or spa. Likewise, pools or spas shall not be installed over or within 60inches (60″) horizontally from an existing underground conductor.

4.4 Clearance fromHazardous (Classified) Locations

Power Company distribution equipment will not be installed in any location classified ashazardous per NEC500. Customersmust provide adequate working clearance (for constructionand maintenance) to ensure that neither Power Company equipment nor personnel are inlocations classified as hazardous. Upon Power Company request, customers shall providedocumentation as defined in the NEC500.4 (A).

4.4.1 Clearance from Fuel Storage Tanks

For information about clearances around fuel storage tanks see ESRWhite Paper-4—FuelStorage Tanks.

4.5 Free-Standing Meter Socket Clearances from Permanent Power Company

Equipment

The customer shall comply with the distances listed in the figures below, in addition to state andlocal requirements.

Figure 8—Free-Standing Meter Socket Clearances from Permanent

Power Company Equipment



2019 PacifiCorp.31


4.6 Clearances Between Equipment Pads and Buildings

The customer shall comply with the distances listed in the figures below, in addition to state andlocal requirements.

Figure 9—MinimumClearances Between Equipment Pads and Buildings

Requirements:1. Distances noted in Figure 9 and Table 9 are from the edge of the equipment pad.

2. If the building has an overhang, the distance is measured from the outside edge of theoverhang.

3. Outside edges of any attachments to the building, such as ramps, and stairs, will beconsidered part of the building perimeter.

4. Distances less than those specified in Table 9 (but not less than the required working space)may be allowed if approved by the appropriate code enforcement authority. This may requirealternate means of fire protection per NECSection 450.27 and NESCSection 152(A)(2),including fire barriers, fire-rated walls, sprinkler systems, oil-containment means, or othermeasures. Use of alternate means of fire protection must be approved by the authorityhaving jurisdiction.

5. The final grade at the location of the transformer should provide oil drainage away from thebuilding. Otherwise, an adequate oil containment means is required.


6. The customer shall conform to all local building codes, insurance regulations, and/or ordin-ances affecting the transformer location.

7. Combustible/non-combustible construction types are defined by respective statebuilding codes.

8. No vegetation over six inches (6″) in height shall be present in the clear workspace(see Figure 9).

9. Trip hazards such as gutters, spigots, etc., shall not exist within the clear workspace(see Figure 9). Curbsmay be acceptable in the clear workspace; consult the Power Companyduring site scoping.

10. A minimum 72 inch (72″) clearance between fire hydrants and metallic pad-mounted equip-ment shall be maintained.This clearance may be reduced to 48 inches (48″) for non-metallicequipment. Greater separation may be required by local ordinances.

11. Where equipment is exposed to vehicle traffic, barrier posts are required; see Section 1.11,and consult the Power Company for installation-specific requirements.

12. Additional clearancesmay be required for other pad-mounted equipment.

Table 9—MinimumClearances Between Oil-Filled, Pad-Mounted Equipment

and Structures, and Structure Openings

Type of FramingClearance in Frontof Framing (ft.)

Clearance to Sideof Framing (ft.)

Vertical Clearancefrom Framing (ft.)

Fire escape 20 10

Doorway 20 10

Window that can be opened 20 10

Solid window 10 5 10

Air vent intake 20 10 25

Air vent exhaust 10 10 25

Combustible surface 8 10

Non-combustible surface 3 10

4.7 Firewalls (BlastWalls)

At locations where the clearances in Table 9 are not met, a firewall (also called a blast wall) maybe constructed. The firewall shall be constructed such that the heat and flame from a dynamicevent are deflected away from a combustible surface or a storage tank.

The firewall shall be approved by the authority having jurisdiction. Consult the Power Companyfor information on firewalls. Also see ESRWhite Paper 4—Firewalls.



2019 PacifiCorp.33

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